Global Patent Index - EP 0279297 A3

EP 0279297 A3 19901114 - PATTERN CONTOURS IN IMAGE PROCESSING

Title (en)

PATTERN CONTOURS IN IMAGE PROCESSING

Publication

EP 0279297 A3 19901114 (EN)

Application

EP 88101696 A 19880205

Priority

  • JP 2571187 A 19870206
  • JP 15200187 A 19870618

Abstract (en)

[origin: EP0279297A2] Method and apparatus for extracting contour lines from a pattern obtained in image processing, which makes it possible to obtain contour lines real-time with a high speed and, moreover, can easily make use of hardware. In embodiments of the invention a simplified discrimination method for selecting those pixels which form the pattern contour is employed. Pixels are grouped into two groups, X-axis and Y-axis groups or, in other words, given two representations, an X-axis representation and a Y-axis representation. In relation to each group or representation the magnitude of gray level gradient of each pixel is compared with those of neighbouring pixels lying in either X-axis directions or Y-axis directions with respect to the pixel under consideration, and the pixel which has the maximum magnitude of gray level gradient among neighbouring pixels is discriminated. This discrimination method is simple and can offer remarkable improved processing. When contour lines determined for the two groups are combined, pattern contours can be easily obtained.

IPC 1-7

G06F 15/68

IPC 8 full level

G06T 5/00 (2006.01); G06V 10/36 (2022.01)

CPC (source: EP US)

G06T 7/12 (2016.12 - EP US); G06V 10/36 (2022.01 - EP US); G06V 10/443 (2022.01 - EP US); G06T 2200/28 (2013.01 - EP US)

Citation (search report)

  • [A] GB 2171272 A 19860820 - MITSUBISHI ELECTRIC CORP
  • [A] COMPUTER GRAPHICS AND IMAGE PROCESSING, vol. 6, no. 5, October 1977, pages 492-501, Academic Press, Inc., New York, US; G.S. ROBINSON: "Edge detection by compass gradient masks"
  • [A] PATTERN RECOGNITION, vol. 10, no. 4, 1978, pages 261-264, Pergamon Press Ltd, Elmsford, US; C.H. CHEN: "Note on a modified gradient method for image analysis"

Designated contracting state (EPC)

DE FR GB

DOCDB simple family (publication)

EP 0279297 A2 19880824; EP 0279297 A3 19901114; EP 0279297 B1 19931229; AU 1127688 A 19880811; AU 583202 B2 19890420; DE 3886560 D1 19940210; DE 3886560 T2 19940421; US 4908872 A 19900313

DOCDB simple family (application)

EP 88101696 A 19880205; AU 1127688 A 19880204; DE 3886560 T 19880205; US 15342688 A 19880205